Generally, the blanks are fed to a packaging machine, e.g. a boxing machine, by picking up devices having a rotating head, and suction means for stripping flat folded blanks from the bottom of a pile, and abutment means for erecting the blanks before their placing in relevant conveyor seats of the packaging machine.
A rotating head device of this type includes substantially mechanisms, e.g. cam and/or epicyclical mechanisms, aimed at operating the above suction picking up means during the head rotation.
Examples of the above devices are described in the U.S. Pat. No. 4,194,442 and in the U.S. Pat. No. 6,503,108.
At present, known picking up devices try to correct the characteristic movement trajectories by applying suitable corrective devices to the moving device, which obviously results in very complicated and considerably bulky mechanisms.
Moreover, the above mentioned devices, described in the cited US patents, pick up the flat surface of the blanks, which are later placed on the conveyors in a conveying station on an opposite flat surface, by turning the blanks by 180 °.
Therefore, it is necessary to perform difficult adjustment operations of the device, when the height or dimension of the used blanks changes.